Operators
and conditions are components of statements. Arithmetic
operators manipulate the values of numbers. "String
operators" work on text strings. Conditional
operators compare the values of strings and numbers in
IF statements. Compound conditions
are built with logical operators.
Special operators are
used in specific situations.

Arithmetic
Operators

Use the
arithmetic operators in assignment statements to perform arithmetic
on numbers. The arithmetic operators do not function inside strings
or conditions.

+

addition

add
two numbers

-

subtraction

subtract one number from
another

*

multiplication

multiply two number

/

division

divide one number by another

String
Operators

+

concatenation

join
two strings (not inside double quotation marks)

.

concatenation

denote
the end of a variable name inside doublequotes

Conditional
Operators

To control
execution of a statement or a set of statements based on the value
of a variable, use an IF statement with a condition. A condition
compares the values of two variables or a variable and a literal
number or literal string.

All operators
are binary, and the general syntax is A
operator B.

If both
operand A and operand B are integers, comparison is based on their
numerical values. Otherwise, an alphabetic comparison is made.

All string
comparisons are case-sensitive. That means "salt" is
not equal to "SALT".

Numbers and Strings

=

equality

numbers
or strings are equal

<>

inequality

numbers
or strings are not equal

Numbers

>

greater than

A
is greater than B

<

less than

A
is less than B

>=

greater than or equal

A
is greater than or equal to B

<=

less than or equal

A
is less than or equal to
B

Strings

INCL

includes

string
A includes string B

NOTINCL

does not include

nstring
A does not include string B

Example
1

_s = "string"

IF _s = "string"
\*
True

IF _s = "string "
\*
False

IF _s = "STRING"
\*
False

IF _s
INCL "ring" \*
True

IF _s INCL "Ring"
\*
False

IF _s
NOTINCL "cow" \*
True

Example
2

_var1
= 10

_var2 = 5 + 5

IF _var2 = _var1 \*
True

IF _var2 <> _var1 \*
False

IF _var1 > 0 \*
True

IF _var2 < 4 \*
False

IF _var1 >= 10 \*
True

IF _var1
<= 10 \*
True

Compound
Conditions

Compound
conditions may be formed from multiple conditions using logical
operators. Use parentheses to group and nest conditions up to
eight levels deep.

AND

logical and

both
A and B

OR

logical or

either
A or B or both

XOR

exclusive or

either
A or B, but not both

Example:

_answers
= 42

_dformat
= "bib"

IF ((_answers
< 100) AND (_dformat = "bib")) /*
True

IF ((_answers
< 100) AND (_dformat = "all")) /*
False

IF ((_answers
< 100) OR (_dformat = "ide")) /*
True

IF ((_answers
< 15) OR (_dformat = "ide")) /*
False

IF ((_answers
< 100) XOR (_dformat = "bib")) /*
FALSE

IF ((_answers
< 100) XOR (_dformat = "ide")) /*
True

Special
Operators

\!

Edit

Edit a command before
sending it to an online host (=> statement).

\>

L-number

Assign
the L-number result of a command to a variable (=>
statement).

#

answer count

Retrieve
the number of answers from an L-number variable.

EXISTS

file existence

Determine
whether a given file exists. EXISTS first checks the User
Scripts folder and then Scripts folder. It sets _$filerror
to zero if the file exists and to a nonzero value if the
file does not exist.